1. Field of Technology
The present invention relates to a non-contact IC (integrated circuit) card having an IC chip and an antenna coil which is connected to the IC chip.
2. Related Prior Art
A non-contact IC card is generally formed with an external cover consisting of two sheets of thin film of an electrically insulating material, an intermediate layer of an attachment material for mutually attaching these sheets, and an antenna coil and an IC chip which are mounted on an inner face of one of the sheets.
With such a prior art type of non-contact IC card, since the IC chip is in the form of a bare chip, the IC chip may become damaged and thereby inoperative, if an external force is applied to the card. For that reason, a reinforcing plate is usually incorporated, mounted over the IC chip, to strengthen the IC chip. However even when such a measure is adopted, the failure rate of such non-contact IC cards is excessively high, being approximately 1%. Such a high failure rate signifies that a sufficiently high degree of reliability cannot be obtained for such non-contact IC cards when these are used in such applications as keys for unlocking vehicle doors or house doors.